Physical model and theoretic criterion of the forecast of water inrush caused by collapse columns

By analyzing the relation and difference between collapse columns and leakage wells, a physical model of predicting water inrush caused by collapse columns was established in combination with the correlative theories of leakage wells, the hazardous area of water inrush in the model was identified. The hazardous area of water inrush between collapse columns and working face divided into three parts:plastic failure zone around the collapse column, plastic failure zone ahead of the mine stope, and permeability zone around the collapse column. A theoretical criterion of predicting water inrush caused by collapse columns was proposed on the basis of plastoelasticity and hydromeehanies. This criterion can be used to predict water inrush caused by collapse columns in a coal mine.